This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In the search for sustainable forms of energy, there has been a large increase in research to develop microorganisms, which can ferment plant material into a combustible liquid fuel such as butanol. However, these fermentation products are toxic at the large concentrations required to meet current energy needs. In order for these fuels to be produced at a practical level, solvent tolerant microorganisms need to be developed. In nature microorganisms live in dynamic environments and must constantly adapt to external stress such as the presence of toxic solvents. Altered metabolism is one of the primary responses to handle external stress. Nuclear magnetic resonance (NMR) spectroscopy has become a useful tool for studying the metabolomics, or metabolite profile of an organism and has the power to allow one to map out complex metabolic responses to external stress. These experiments will provide information that will be useful for understanding how microorganisms adapt to external stress. Furthermore, these experiments will provide a guide for developing microorganisms, which are more tolerant to butanol, a promising future source of biologically derived energy.